I have been having an issue with proportional editing
It's a bit hard to tell what's going on ... (We can't read your mind, what is 'the doughnut in tutorial 2.'?).. but 2 points might help.


G and GG are different operations. G is Grab, a free translation in screen space. GG is Vertex Slide, which will slide selected vertices down adjacent edges. G can be proportional. Proportional Editing has no effect on GG.
When editing proportionally, you should be able to see a circle in the viewport representing the radius of the falloff. If you can't see it, and the whole object moves, the falloff is large enough to encompass all the object's vertices, and may be so large it is off-screen. Try using the scroll-wheel to bring it down into view.